The popularization of devices, such as head mount display devices and spectacle display devices, that can present pictures right in front of a user's eyes has recently been exploding. Along with this popularization, various devices that use results of detection of eye movements, as well as devices that are used with hands, such as mouses and joysticks, have been proposed and sold as devices for operating computers.
There have conventionally been proposed various methods for detecting an eye movement. Typical examples of these methods are the EOG method, the sclera reflection method, the cornea reflection method, and the search coil method. In the EOG method, the presence in a corneal section of a positive potential that is higher by 10 to 30 μV than that in a retinal portion is detected by electrodes placed around an eye. In the sclera reflection method, a pupillary movement is detected by a visible camera on the basis of a difference in reflectivity between the iris and pupil of an eye and the white of the eye. In the cornea reflection method, an eye is irradiated with low-intensity infrared radiation, and a reflection of the infrared radiation by the cornea is detected by an infrared camera. In the search coil method, the position of a contact lens around which a coil is wound is detected.
However, these methods have the following shortcomings. The EOG method causes the user the inconvenience of the electrodes sticking to the skin, and the electrodes are vulnerable to electromagnetic noise, sweat, and sebum. The sclera reflection method requires image processing and therefore entails increases in power consumption and weight of a device that employs this method. The cornea reflection method requires irradiation of the eye with light and image processing and therefore entails increases in power consumption and weight of a device that employs this method. The search coil method causes the user the inconvenience of wearing contact lenses.
Various technologies for alleviating the shortcomings of the EOG method have conventionally been proposed. One of the technologies is eyewear disclosed in PTL 1. This eyewear includes a frame, a pair of nose pads, and first and second electrodes provided on the respective surfaces of the pair of nose pads to detect an eye potential.